Electric switch



June 17, 1930. A G, HQRVATH ELECTRIC SWITCH Filed Nov. 14, 1928 2 Sheets-Sheet 1 mm om v m E 4 Juan! flm'uorw HOR WITH,

NW a m W. G. 3 -W\ NQ\ Q. mm wm mm mm C t h mm mm a R w as Q 3 g u. g n m n 3 n June 17, 1930. o v H 1,765,016

ELECTRIC SWITCH Filed Nov. 14, 1928 2 Sheets-Sheet 2 25 4o T6 28 I k {l 1 1 \J/ Patented June 17, 1930 rim T121) STATES PATENT o-FFIc onIo, Assrcmo'n TO 01110, A coaeonnrron or 01110 THE DAYTON PUMP AND ELECTRIC SWITCH Application filed November My invention relates to electric switches.

It is the object of my invention to provide an electric switch which is operated by hydraulic or pneumatic-pressure, orv other motive power.

It is an objectparticularly to provide a switchfor air compressors and pumping apparatus, in which the state of the pressure in the apparatuswill control the switch to open or close it, in orderoto maintain a' predetermined pressure in the system.

It is a further object of my. invention to provide a switch. having one or more of the ollowing characteristics:

(a) A snap opening of the switch so that it will be. immediately opened without arcing.

(b) The locln'ng of the switch in closed position until suflicient power has been' stored up in the opening mechanism to insure immediate and positive opening of the switch.

. (c) A secondary safety means of pos1- tively opening the switch in the event that a dangerous amount of pressure has been accumulated inthe system-and the prima means of opening the switch has failed to open it.

(d) Means of movingthe switch contacts into and out of engagement with each other so that their faces will always be maintamed in parallel relationship.

' into Referring to the drawings:

Figure 1 is an elevation of the switch with the cover, diaphragm and diaphragm chamher in section, showing the switch parts in position about. to snap the contacts out of engagement with one another.

Figure 2 is a similarwiew, mechanism in position to snap the contacts engagement with one another. Figure 3 is a similar view, showing the parts in position to snap out' when the primary actuating mechanism showing the and the secondary safety mechanism is: about tovforce out the contacts from engagement with-one another.

Referring to the drawings-in detail, 1 is a sleeve constituting a connecting means for a pressure pipe connected into the system.

7 ing plunger,

has failed 7 14, 1928. Serial No. 319,419.

The passageway 2 rovides the su 1 line for the diaphragm chamber 3, th d tb p of which is closed by the flexible On this diaphragm is mounteda reciprocatreceiving sleeve 5 that reciprocates through the bottom 6 of the switch casing 7. Suitable openings 8 are provided in this casing for the introduction of electric cables that are connected to the stationary and movable contacts of the switch.

The hollow sleeve 5 .contains the thrust pin 9 that is journalled through the block 10 on the pivot 11 in the arm 12. This arm 12 is pivoted at 13 and moves about that pivot. The pin 13 is mounted in the side walls of the casin 7.

The righthand end of the arm ally connected'at 14 to a pitman- 15. This pitman is pivoted at 16 to the guide link 17 at the righthandside of the link. The pitman 15 is also pivoted at 18 to the righthand 12 is pivotside of the main actuating lever 19. This lever is pivoted upon the pin 20, which is stationarily mounted in the ears 21 of the casing 7 The extreme end of the lever 19 supports upon the pivot pin 22 a bell crank consisting of a cam arm 23, havingcam surfaces 24 and 25'and a spring arm 26 through which is loosely mounted an adjustable screw link. 27,, which carries. the main actuating spring 28, the lower end of which is hooked over the free end 29 of. the lever-12f Adjustments in the tension of this spring are effected by the position of the nut 30 on the adjusting screw 27. The brackets 31 on the casing 7 support the bar 32 that minals and contacts 33. Movable contacts 34 are carrie upon the transverse spring plate 35, and in turn are connected by the cable 36 on the switch arm 37. This switch arm reciprocates in a straight line, substantially, being guided by the bar 32 and the link 17.

It carries at its lower end a roller 38 that! engages with cam cam arm 23. It safety guide link 17, which is pivoted on the stationary pin 39 loosel Such pin is cardiaphragm 4.

carries the stationary tersurfaces 24 and 25 of the 7 is also engaged by the ried in the side walls of the casing 7 but 1y cause the cam arm 23, with its cam surthere is a space around this pin so that movefaces, to press the roller 38 to jerk the switch ment of the safety ide link can take place arm and its movable contacts out of engagewithout engaging t e pin. ment with the stationary contacts, due to The latch is also pivoted on the pin 39. the ener in the spring 28, which energy 7 This latch has a dual function. It normally i delaye from being expended until the acts through the detent 41 operating in the diaphragm shall have moved a predetern tch 42 in he swi ch arm 37 to h l h mined amount, at which time the switch switch in closed position until the spring 28 arm will be unlatched by the detent 41, being has stored up such energy as to positively withdrawn from the notch 42. As soon as and promptly break the contacts upon rethe unlatching is effected the spring 28 will moval of the detent 41 from ,the notch 42. cause the cam arm 23, engaging the roller It will be noted that this detent is adjustably 36, to press the switch arm 37 downward mounted on the end of the member 40 by thereby breaking the electrical contact. means of the set screw 43 working in the The ositions of the parts for accomplishso slot 44. ing t is purpose are illustrated in Figure It will be further observed that the mem- 3, .In Figur 1 th parts are shown with ber40 is provided with its own detent head th detent 41 just about to be disengaged and cam surface 45, which constitutes a from the notch 42, After the detent 41 safety cam surface whi is adjus to p is disengaged from the notch 42 the pressure the latch 41 from its notch 42 in the event of the s ring 28, acting upon the arm 23 that it does not do so,- and in the further ill cause th bar 37 t lower. When the event that the pressure becomes sufficient to pressure h b li d the di h m move the roller 46 against the cam surface ill b l d d th Parts ill assume 45, which will occur if excessive pressures again a iti i ilar to that hown in exi t n the y m. and have not been Figure 2, in which the cam arm 23 is shown determined amount thereof has been accumlieved by the breaking of the switch at lower in a position beneath the roller 38. When. j Such (3011511131911 15 shown In the parts are in the sition shown in Figure lghl'e The f 40 15 p h y h h 2 the pressure wit in the cavit 3 on the on the safety hnk 17, and is yi l g y' diaphragm 4 will cause the righthand end P Into latchmg Poslhoh y the of the lever 12 to be raised and carry with p it the link 15 and the lever 19. In moving 1 M th d f ti the level!1 191rhe pagvl am;1 23 is fofrctleld -'sttero er38 uetoteactiono te Normally, the pressure system will be i op rating with a powersource such as an hprmgh g z llember 37 electric motor controlled by this electric 1s agam h an con he 15 ma switch, the motor driving appIaratus to build Safety mechanism u pressure in the system. t is the object o to stop motor and hi: $21,112:; 3:22;: email 2:: the hmhhhg up of the pressure when a Pmroller 46 does not engage it, the roller 46 dated in the system will come in engagement with the cam sur- In Figure 1 the parts are shown in this face 45 and force the lock out of enfigement with the switch arm so that itcan moved operatmg cohdlhoh lust it; E; fig to break the contacts of the switches. This no 46 has engaged the cam Shh occurs, for instance, if the normal pressure detent 41 to move it out of sition from a l the notch 42. As the diaphnhgm 4 lifts it should be twenty Pounds and the e moves the sleeve 5 and the pin 9 upwardly e through the roller 46 takes Place at so that the righthand side of the lever 12 thlrty-five Pounds pr moves upwardly about the pivot 13, while 15 an hddlhohhhsafety mehhhmsm the lefthand side moves downwardly, storthe Safety h whlch "l I ing energy in the spring 28. downwardly on its lefthand side a suflicient The pitman 15, therefore, moves upwardly m to efiect e hhhltchmg and and carries with it the safety link 17 about q s of the movable a s? the w its pivot 39. The result of the movement h 3 to h the l l i) 1f t a of the pitman 15 is to he the lever 19 Pr becomes excewvee): rought about its pivot 20 and thereby carry the about by the unusual amount of movement, roller 46 to a position where it will engage under s ch condition f the pitman 15, the cam surface 47 to move the detent 41 which will move the lefthand end of the 1g out of engagement with the'notch 42. safety link 17 downwardly about the sta- While this is occurring the energy stored tionary ivot 39 and thereby pull the switch in the spring 28 is increasing and t e presarm 3 iownward and its movable contacts sure of the cam surface 24 on the roller 38 out of engagement with the stationary is increasing, it being the object to eventualcontacts. 1i

filming operation The closing operation takes places when the ressure must be built up by the "closing of the electric circuit. The parts in Figure 2 are in position about to close. When the pressure has'decreased to a point that the diaphragm has returned to the position shown in Figure 2, the cam surface 24, which has been on top of the roller 38, will snap beneath the roller to put the cam surface '25 underneath it, thereby serving through'the tension of the spring 28, to force the movable contacts and the safety arm 37 into closed position, whereupon the latch 41 falls in the notch 42 to hold the switch in that position. The cam surface 25 stays beneath the rolle 38 until the pressure builds up to the poi ,t where the switch must be opened, whereupon the cam surface 24 is snapped into position above the roller to force the switch arm into its outermost position, as shown in Figure 1, where this has occurred and the switch is about to open.

' he passageway 2 is provided with alternate rings 50 and notched plates 51 having 'notches 52, the apertures in the rings and of levers the notches slightly overlapping so that ill-- creased pressure may larger opening without mits of a'more accurate and flexible mechanism being secured.

desire tocomprehend within my invention such modifications as may be clearly embraced within my claims and thescope of my invention.

Having thus fully described my invention, what I claim is new and desire to secure by Letters Patent, is:

1. n a pressure switch, a pressure-operating diaphra a system of levers, a spring operated thereby for storing energy, a cam moved by the spring, a switch arm and roller engaged by the cam, movable contacts on the switch arm, stationary contacts, latch means for holding the switch arm in closed position, means on the system for detaching the latch upon a predetermined amount of energy being accomplished in the spring, a lever of the system of levers connected to the switch arm for positively moving the switch arm in the event the spring and associated mechanism do not, and supplemental unlatching mechanism adapted to unlatch the latch at a higher pressure in the event the normal unlatching means does not operate.

2. In a pressure switch, a pressure-operbe secured with a ating means, a lever operated thereby with spring on the other, -mounted on a switch casing,

a stationarv pivot, a pitman on one end, a a second lever pivotally a bell crank on the end of the second lever having a cam on one arm, means of attaching said sprlng on the other arm, a

clogging. This peroperation, an adjustably mounted 'justing said switch arm, m'ovablecontacts thereon, stationary contacts,- a latch for latching the switch arm in closed position, and means on the second lever for unlatching said latch at a predetermined point. I

3' In a pressure switch, a pressure-operating means, a lever operated thereby with a stationary pivot, a pitman on one end, -a spring on the other, a second lever pivotally mounted on a switch casing, a bell.crank pivotally mounted on having a cam on one arm, means of attaching said spring on. the other, a switch arm, movable contacts thereon, stationary contacts, a latch for latching the switch arm 1n closed position, means on the second lever for unlatching said latch at a predetermined point, and a safety levervloosely pivoted on said casing and pivoted at either end to said pitman and the switch arm,-whereby upon a predetermined additional amount of movement due to excess pressure upon the diaphragm the safety lever will positively move the switch arm out of engaging position, said latching means comprising a normally operative latching and unlatching means and an unlatching means operative under abnormal conditions.

4. In a pressure switch, a pressure-operating diaphragm, a system of levers oper- .1

ated thereby, a spring connected thereto for the storage of energy, a cam actuated by the spring, a switch arm, a cam roller thereon, a latch for holding said switch arm in closed position operating in a notch thereof, said latch comprising a latch member, a cam surface thereon for abnormal unlatching detent for engaging said notch having a cam for normal unlatching operation, means for adjusting said detent and cam on the latch, and roller means on the-system of levers for engaging said respective cams for normal and abnormal unlatching operations of the movable contacts on the switch arm and stationary contacts.

5. In a pressure switch, a pressure-operthe end of the lever ating diaphragm, a system of levers operated thereby, a spring connected thereto for the storage of energy, a cam actuated by the spring, a switch arm, a camroller there on, a latch for holding said switch arm in closed position operating in a notch thereof, said latch-comprising a latch member, a cam surface thereon for abnormal unlatching operation, an adjustably mounted detent for engaging said notch having a cam for normal unlatching operation, means for addetent and cam on the latch, roller means on the system of levers for engaging said respective cams for normal and abnormal unlatching operations of the movable contacts on the switch arm and stationary contacts, and yielding means between said movable contacts and said switch arm.

. having means arm, a roller on able contacts on said switch arm,

otedat one end of the lever, and a spring at the other, a second lever substantially parallel to the first actuated by the pitman and pivoted on the casing at one end, a bell crank at the other end of the second lever having means to attach thespring to one arm and angular cam surfaces on the other arm, a vertically reciprocating switch arm, a roller thereon for engaging said cam, a safety link pivotally connected at either end to said pitman and said switch arm and loosely pivoted on said casing, a latch carried on said safety link, a pivotal yielding means for maintaining said latch normally in latching position, an unlatching cam, and a latching nose on said latching means, said nose engaging in a notch in the switch arm, a roller on the second lever for engaging said cam for unlatching the latch, movable contacts on said switch arm, and stationary contacts carried by the casing.

, 7 In a pressure switch, a support comprisin a pressure passageway in the bottom 0 adiaphragm chamber, a diaphragm, a casing enga ing the margins of the diaphragm and orming the switch and lever supports, a lever actuated by said diaphram pivoted on the casing, a pitman pivoted-at one end of the lever and a spring at the other, a second lever substantially parallel to the first actuated by the pitman and pivoted on the casing at one end, a bell crank at the other end of the second lever to attach the spring to one ar cam surfaces on the other arm and angul switch arm,

arm, a vertically reciprocating a roller thereon for engagin said cam, a safety link pivotally 'connectec at either end to said pitman and said switch arm and loosely pivoted on said casing, a latch carried on-said safety link, pivotal yielding means for maintaining said latch normally in latching position, an unlatching cam, and a latching nose on said latching means, said nose engaging in a notch in the switch the second lever for engagcam for unlatching the latch, movstationary contacts carried by the casing, and means for adjusting the position of said cam and said detent on the latching means.

8. In a pressure switch, a support comprising'a pressure passageway in the bottom of a diaphragm chamber, a diaphragm, a casing engaging the margins of the diaphragm and forming the switch and lever supports, a lever actuated by said diaphragm pivoted on the casing, a pitman piving said oted at one and of the lever and a spring at the other, a second lever substantially parallel to the first actuated by the pitman and pivoted on the casing at one end, a bell crank at the other end of the second lever having means to attach the spring to one arm and angular cam surfaces on the other arm, a vertically reciprocating switch arm, a roller thereon for engaging said cam, a safety link pivotally connected at either end to said pitman and said switch arm and loosely pivoted on said casing, a latch carried on said safety link, pivotal yielding means for maintaining said latch normally in latching position, an unlatching cam,

and a latching nose on said latching means, said nose engaging in a notch in the switch arm, a roller on the second lever for engaging said cam for unlatching the latch, movable contacts on said switch arm, stationary contacts carried by the casing, means for adjusting the position of said cam and said detent on the latching means, and a supplemental safety cam on said latching means.

In testimony whereof, I afiix my signature.

ANTHONY G. HORVATH. 

